Facsimile apparatus



Jan. 11, 1944.

M. ARTZT 2,339,133

FACS IMILE APPARATUS 2 sheets-sheet 1 Filed'Aug. 25, 1942 INVNTOR aurel'z 0 BY Q ATTQRNEY Jan. 11, 1,944. M, AR-rz-r 2,339,133

FACSIMILE APPARATUS Filed Aug. 25. 1942 2 Sheets-Sheet 2 INYENTOR Mar .Zrz

ATTORNEY.

Patented Jan. 11, 1944 UNITED STATES PATENT OFFICE FACSIMILE APPARATUS Maurice Artzt, Haddonfleld, N. J., assignor to Radio Corporation oi' America, a corporation of Delaware Application August z5, 1942, serial No. 456,000

rc1. 17a-1a) 17 Claims.

positioned. This cylinder is then rotated at a predetermined constant rate, and during the rotation of the cylinder, a beam of light of reduced cross section is projected against the outside surface of the cylinder in order to perform a scanning action. Light reiiection from the surface is then directed against a light responsive cell in order that the variations in reflected light will produce variations in the produced current representative of the subject matter appearing on the copy. As the drum is rotated, the spot of light and the photo-cell are moved longitudinally with respect to the drum in order that bi-dimensional scanning may be accomplished.

Simultaneously with the scanning operation, synchronizing or framing impulses are generated by appropriate means for providing a framing impulse for each revolution of the drum in order that facsimile receivers may be maintained in proper synchronous operation with respect to the transmitter. As is well known to those skilled in the art, the picture signals produced hyythe photo-cell or the light responsive element at the transmitter are, after appropriate amplification, transmitted to the receiver either by direct wire connection or by a radio link through the usev of va modulated radio frequency carrier. Simultaneously, the synchronizing or framing impulses are transmitted to the receiver so that at the re- .ceiver the picture signals may be utilized to pro- .duce a facsimile copy of vsubject matter positioned on the scannerdrum in the transmitter.

An electric motor is normallyprovidedfor rotating the scanner drum at the transmitter, andv it is preferable that the motor operate at substantially constant speed in order to facilitate in. imaintaining synchronous operation at the rel ceiver, since it might not be possible for the mov-,- ing elements at the receiver to follow excessively rapid changes in speed of the scanner drum at the transmitterdue tothe mechanical inertia of the moving parts of the receiver.

Inasmuch as the-copy mustr'be attached to the f continue the operation of the transmitter, in

which case it is preferable to be able to remove the scanner drumfrom the transmitterjwithout the necessity of actually stopping the driving motor, and without discontinuing the transmission of the synchronizing or framing impulses. Furthermore, should the scanner drum be removed from the transmitter while the driving motor is. still permitted to run, it is necessary to provide., some means for again placing the scanner drum in the transmitter and for coupling the motor to the scanner drum in order that the drum may again be rotated at its normal scanning rate. In addition to imparting rotary motion to the drum, it is also necessary that the drum be properly phased with respect to the coupling or chuck' mechanism for driving the drum, in order that the synchronizing signals will occur at proper time intervals with respect to each scanning revolution of the drum. This is because of the fact that the synchronizing or framing signals are normally derived from a continuously rotating part of the transmitter, and a proper phase relation or orientation of the scanner drum or cylinder is necessary with respect to the chuck as sociated with the drum.

Accordingly, it is one purpose of the present invention to provide in a facsimile transmitter, structural means whereby itis possible to remove the scanner drum from the transmitter without the necessity of discontinuing the operation oi the driving motor.

Another purpose of the present invention resides in the provision of means for again positioning the scanner drum in the transmitter while' the driving mec/ha'nism is in operation.

Still another purpose of the present invention resides in the provision oi' means whereby the facsimile transmitter scanner. drum may be brought up to proper rotational vspeed through the use of a clutch mechanism, and after proper rotational speed is obtained further means are provided for properly framing or phasing the position ofA the scanner drum with respect to the chuck .driving mechanism.

A still further purpose of the present invention resides in the provision of a tail stock assembly for supporting the end of the scanner drum opposite the driven end such that the scanner drum maybe' rotated and such that the scanner drum may be released from both the Chuck mechanism and the tail stock after the scanning operation has been completed.

Still another purpose of the present invention resides in the provision of a tail stock assembly which may assume any one of three positions, one of the positions being the released or inoperative position, another position being the starting position during which time the scanner drum is brought to proper rotational speed, and the third position being the running 'position in which the scanner drum is properly phased rotationally with respect to the driving clutch.

Various other purposes and advantages of the present invention will become apparent to those skilled in the art from the following detailed description and claims, particularly when considered in connection with the drawings, wherein like reference numerals represent like parts and wherein Figure 1 shows a preferred form of the present invention with the clutch assembly, the scanner drum and the tail stock assembly in the starting position; I

Figure 2 shows the present invention with the clutch assembly, the scanner drum and the tail stock assembly in the running or scanning position;

Figure 3 shows an end view of the clutch assembly for driving the scanner drum; and

Figure 4 shows a perspective view of one end of the scanner drum.

Referring now to the drawings, and particularly to Figure 1 thereof, a facsimile transmitter scanning drum III is provided upon which is positioned the copy to be transmitted. Normally the copy is wrapped about the periphery of the drum and is retained in position thereon by mean of an appropriate securing means I2. Inasmuch as the present invention is not concerned with the specific construction of the scanner drum or the structure supporting the paper, that portion of the drum intermediate the ends thereof will not be described in detail, and, furthermore, for simplicity and in order to conserve space only the end portions of the drum are shown.

The live spindle or driven end of the drum includes a central axial aperture or recess which serves as a bearing member, the recess being lined with an appropriate bearing surface such as brass or Oilite" I3. Attached to the end of the scanner drum is. a circular plate I4, the plate being secured to the drum by means of a plurality of screws or other appropriate fastening means I6. The plate member I4 or the end face of the scanning drum is provided with a radial notch or recess I8, the purpose of which will be explained later.

The opposite end of the scanner drum has a reduced portion 28 which is bored along its axis to provide a bearing, and an appropriate bearing surface 22 similar to the bearing surface I3 on the opposite end of the drum is provided.

The mechanism for driving the scanner drum includes a motor 24 which is coupled to the shaft 26. The shaft is supported by an appropriate bearing surface 28 attached to a wall structure 36. A sleeve 32 is attached to the shaft by means of a pin 34. The sleeve is provided with an annular driving member 36 which forms one face of a clutch mechanism. A ball bearing, including an internal race 38 and an external race 40, is slidably positioned on the sleeve 32 in order that it may move axially with respect to the sfeeve. Attached to the external race 40 of the ball bearing is an annular driven member 42, and a cap disk 44 is attached to the annular member 42 by means of screws or other appropriate fastening means 46 in order that there can be no relative motion between the annular member 42 and the external race 40 of the ball bearing.

The annular member 42 includes two plane faces normal to the axis of the sleeve 32 and normal to the axis of the shaft 26. One of these faces is provided with a clutch facing 48, and the other is provided with a clutch facing 50. These two clutch facings may be made of leather or other appropriate material, the facings being attached to the annular member 42 by means of cement or other appropriate securing means. The clutch facing 48 normally cooperates with the annular driving portion 36 of the sleeve 32 in order that the rotation of the sleeve 32 may impart a rotary motion to the annular driven member 42. The clutch face 48 is held in cooperating contact with the annular member 36 by means of a compression spring 52 which is positioned between the longitudinally slidable lball bearing race 38 and a collar.54 that is permanently attached to the sleeve 32 by means of set screws 56. When no force is applied to the annular driven member 42 to separate the clutch face 48 from the annular driving member 36, the clutch will cause the annular driven member 42 to rotate with the main driving shaft 26.

The clutch face 50 is arranged to cooperate with the plate I4 that is attached to the end of the scanner drum I0. In order that the scanner drum may be guided into proper position and may be axially aligned with the main driving shaft 26, the end of the shaft 26 adjacert the scanner drum is tapered slightly in order to act as a guide when the bearing surface I3 is brought into contact with the end'of the shaft 26. When the scanner drum is forced against the clutch facing 58 by means of'the tail stock assembly, the construction of which will be explained later, a rotary driving force for' imparting a rotary motion to the previously stationary scanner drum will then be transmitted from the motor 24 through the shaft 26, pin 34, sleeve 32, the clutch including face 48 and annular driving member 36, through the annular driven member 42 to the clutch face 50. This will permit the scanning drum to be brought up to proper rotational speed corresponding to the speed of the main driving shaft 26.

i The rotating sleeve 32 has attached thereto a somewhat resilient spring support member 62 which is substantially semi-circular in shape, the

ends of the semi-circular spring member 62 be- A ing attached to the sleeve 32 by means of screws or other appropriate securing means 64. The spring support member 62 has attached thereto a roller 58, the roller being secured by means of a bolt and nut or other suitable means. In

` Figure 3 is shown an end view of the clutch, and

in `this view the relationship of the roller 58 and the associated elements for supporting the roller are clearly shown'.

The roller is arranged to cooperate with the" drum to be disengaged from the driving mechamsm. As the scanner drum begins to slow down.'

by reason ofthe disengagement of the clutch.

the roller 58 (which is then in contact with the face of the plate I4) will eventually drop into the radial recess I8, thereby fixing the relative rotational position of the scanner drum with respect to the driving shaft 28 and the sleeve 82, since the roller 58 is permanently attached to the sleeve 82. Rotational forces will then be transmitted through the semi-circular spring member 82 and the roller 58 to the end face |4 oi' the printer drum, inasmuch as the roller 58 is then positioned in the recess 8.

Figure 2 shows the final or running position of the clutch mechanism with the scanner drum cooperating with the roller 58. In Figure 2, the elements have applied thereto the same reference numerals as are applied to the corresponding parts in Figure 1. When the scanner drum is in its final operating or running position, it will be noticed that the end of the shaft 26 extends an appreciable distance into the bearing I8 in order to rigidly support the scanner drum, and in order to prevent any possibility of radial movement of the drum. In lthe running position, as shown in Figure 2, the clutch faces are not effective for transmitting rotational forces (since clutch face 48 is disengaged from the cooperating driving member 88), nor is the roller bearing 38-48 in operation since the entire clutch mechanism then rotates as a unit.

For imparting the desired longitudinal movement to the scanner drum in order to operate the clutch mechanism as described above, a tail spindle structure is used such as shown at the right hand portion of Figures 1 and 2. Through the operation oi' this tail structure, the scanner drum may be moved the'proper longitudinal amount in order to bring the scanner drum up to its proper rotational speed during the starting interval, and in order to subsequently bring the scanner drum into proper cooperative position with the roller 58 in order that the scanner drum may be properly phased and positively driven by means of this cooperation. A

The tail-spindle structure includes a shaft' 18 which is supported in a housing or other stationary structure 12. On the` shaft 18 is positioned a slidable cylinder 14, the cylinder 14 being normally urged against a shoulder 18 made integralwith the shaft 18. 'I'he shoulder 16 may, however, be in the form of a ring retainedl in proper position by means of set screws. The cylinder 14 is urged against'the shoulder 18 by means of compression spring 18, the spring cooperating with a ring 88 secured to the rod 18.

Another ring v82 is also provided for limiting motion of the rod 18 in the direction toward the right in the drawings, and normally the rod 18 is urged in that direction by means of compression spring 84. This spring is positioned between the wall 12 and a shoulder or washer 86 at the end of the rod 18.

In the normal released position of the rod 18, the spring 84 urges the rod in its extreme right position, indicated by the dotted end portion of the rod 18 in Figure 2, whereas in the starting position the shaft occupies a position such as indicated in Figure 1. When the facsimile transmitter is in its final running or operating position, the shaft 18 is in a position such as indicated in Figure 2.

In-order that the rod 18 may be moved the desired amounts, a ratchet mechanism is provided.

'Ihe cylinder 14 is provided with two annular grooves 88 and 98 with which cooperate two pawls 82 and 94. The pawl 92 is pivoted on an operating lever 98 at the pivot point 98, while the operating lever is pivoted on the pin |88. yIn order that the pawl 92 maybe urged in the direction of the cylinder 14, a tension spring |82 is connected between the pivot point |88 and the end of the pawl lever 92. Furthermore, in order that the operating lever may be retained in its normal position, a second tension spring |84 is connected between the pivot point 98 (or the end of the operating lever 96) and a stationary part of the housing or the wall 12.

When the tail stock mechanism is in its complete o or disengaged position, indicated by the dotted end portion of rod 18 in Figure 2, the pawl 92 normally rests in a. position to cooperate With the annular ring 88. Actually, the pawl 82 is not permitted to touch the cylinder 14 when the operating handle is in its released position. since the stationary vertical pin |86 cooperates with the pawl 92 to prevent the operating end of the pawl from cooperating with the cylindrical member 14 until after some initial movement has been imparted to the operating lever 96. When the operating lever 98 is moved in a counterclockwise direction about the pivot point |88, the pawl 92 engages the annular ring 88 to slide the rod 18 forward a predetermined amount against the action of spring 84, the sliding force being transmitted through the somewhat' stronger spring 1,8, 'The pawl 94 then drops into the annular ring 88 to retain the rod 18 in that position. 'Ihe pawl 94 is pivoted about point |88, and this pawl is urged in the direction vof the cylinder 14 by means of compression spring II8.,

This operation causes the end face I4 of the scanner drum to engage clutch face 58 to cause rotation of the drum through clutch 36--48. After the scanner drum has been brought up to its proper rotational speed, the operating handle is then again rotated in a clockwise direction at which time the pawl 92 cooperates with the annular groove 98, as indicated in Figure 2, to further slide the rod 18 toward the left to thereby axially move the scanner drum in the corresponding direction to disengage clutch faces 48 and 36. Relative rotational motion between the scanner drum and the driving member 36 is then permitted until the roller 58 encounters the radial notch or groove i8, at which time a slight longitudinal movement of the scanner drum (due to i compression spring 18) causes the roller 58 to positively engage the radial notch I8 to preclude any further relative motion, and to afford a fixed positive driving action for the scanner drum.

The principal purpose of spring 18 is to provide an elastic medium through which a longitudinal force is supplied to the scanner drum, particularly after the drum has been brought up to proper rotational speed. The spring 18, therefore, produces a biasing force on the scanner drum in the direction of the clutch mechanism so as to deil-A nitely cause the roller 58`to firmly seat in the radial groove i8 and to be firmly held in that position to prevent any relative motion between the clutch 'mechanism and the'scanner drum. During the operation of the machine, the spring 18, l

therefore, maintains sufficient longitudinal force on the scanning drum to prevent relative movement between the scanner drum and the clutch mechanism which would, of course, destroy the proper phase relationship between these elements of the apparatus. f

After the copy has been scanned and it is desired to change the copy on the drum, or if a plurality of drums are provided and it is desired to |08. This results in disengagement of the pawl 94 from the annular ring 80 (see Figure 2), and by reason of the spring 84, the rod I is returned to its off or inoperative position. When this occurs, the force of the spring which is transmitted through the annular driven member 42 to the clutch face 50, and from there to the scanner drum, causes the scanner drum to move to the right, completely disengaging the clutch, the inertia being sufficient to cause the scanner drum to fall off the spindle 26. At the same time, the shaft 'I0 has moved longitudinally an amount sufficient to completely release the opposite end of the scanner drum. The scanner drum then drops a slight amount and is caught by the semicircular support; brackets I I4 and I I6, the former cooperating with the clutch end of the scanner drum, and the latter cooperating with the opposite end of the scanner drum. Since the scanner drum was initially spinning at its normal scanning rate at the time it was released, the drum will continue to rotate in the semi-circular arms of the support brackets I I4 and II6 until the energy is dissipated by friction between the drum and the support brackets. The drum may then be removed manually from the apparatus, and a new drum (or the same drum loaded with a new copy) positioned upon the stationary support brackets I`I4 and II 6. With the drum in such a position, it is then only necessary to opcrate the member 96 through twosteps, one of which brings the drum up to its proper operating speed, as described above, and the other finally brings the drum into cooperating with the roller 58 to thereby assure proper framing of the drum with respect to the driving mechanism and to thereby provide a positive driving medium.

It will be noticed in Figures 1 and 2 that the paper holding means I2 provided on the drum occupies the same annular position as the radial groove I8. It is not necessary that this relationship be present; however, some phase relationship must exist in order that the picture signals produced by the scanning operation may be properly phased with respect to the synchronizing or framing impulses that are produced by mechanism, not shown, associated with the transmitter driving mechanism. I

Figure 4 shows a perspective View of the clutch end of the scanner drum, and in this view the bearing surface I3, the radial notch I8, and the u paper holding means I2 are clearly shown.

From the foregoing it may be seen that a new and improved clutching arrangement for facsimile transmitters has been provided, whereby it is possible to remove the scanner drum from the transmitter without the necessity of actually stopping the transmitter. This is of particular advantage, since changing of the drum occupies only e relatively short space of time, and if the entire transmitter mechanism were stopped, naturally the receivers will lose frame and synchrotnism completely so that it would be necessary to sired, and where it is desirable to frequently and rapidly change the subject matter being scanned and reproduced. In such dupiicators, the print-r ing mechanism is generally directly coupled to the scanning .mechanism and may, in fact, be rigidly coupled to the shaft 26 shown in Figures l and 2'. In such a mechanism, no synchronizing or framing impulses are necessary, since both the transmitter and receiver operate as a unit, but it is still vital that the scanner drum III bear a predetermined rotational position with respect to the printer drum, and more particularly, with respect to the helix on the printer drum. When the apparatus is used in connection with a facsimile duplicator, the worm drive shown in Figure 1 for rotating shaft II8 may be used'to impart motion to the scanning head, or to drive the paper feed mechanism in a manner such as shown and described in Blain applications Serial No. 464,094, filed October 31, 1942, and Serial No. 460,615, filed October 3, 1942.

Although the present invention is 4described somewhat in detail as to mechanical features, it is to be understood that various and divers modifications may be made in the present invention without departing from the spirit and scope thereof, and it is desired that any and all modlilcations be considered Within the purview of the present invention except as limited by the hereinafter appended claims,

Having now described my invention, what I claim is:

1. A facsimile apparatus including a drum member, driving means for rotating said drum including a motor and clutch assembly, a head spindle associated with said clutch assembly for supporting one end of said drum, said clutch assembly including a clutch 'i'ace arranged to cooperate with said drum, and means for moving said drum longitudinally on said head -spindle to engage the drum with the clutch face whereby said drum may be driven by the driving means.

2. A facsimile transmitting apparatus including a scanner drum, driving means for rotating said scanner drum including a motor, a clutch assembly interposed between said motor and said scanner drum, a head spindle associated with said clutch assembly for supporting one end of said drum and for maintaining axial alignment of said drum and .clutch assembly, said clutch assembly including a spring pressed clutch face arranged to cooperate with said drum, and means for moving said drum longitudinally on said head spindle whereby the end of said drum may be brought into engagement with said clutch face to rotate said drum by said motor.

said clutch assembly for supporting one end of said drum, a tail assembly for supporting the other end of said drum, said clutchassembly including a driving and a driven clutch-member, spring means for normally engaging the driving and driven members whereby ythe driven member may be rotated by said driving member, a second clutch face associated with said driven member, said second clutch race being arranged to cooperate with said drum, and means to move said drum longitudinally on said head spindle to engage the drum with said second clutch lace whereby said drum may be rotated by said driven member.

4. A facsimile apparatus including a scanner drum, driving means for rotating said drum including a motor and clutch assembly, a head spindle associated with said clutch assembly for supporting one end of said drum, a tail stock assembly for supporting the other end of said drum, said clutch assembly including a driving and a driven clutch member, spring means for causing the driving and driven members to be normally engaged whereby the driven member may be rotated by said driving member, a second clutch face associatedV rwith said driven member, said second clutch face being arranged to cooperate with said drum, means including said tail stock to move said drum longitudinally on said head spindle to engage the drum with said second clutch face whereby said drum may be rotated by said driven member, and means including said tail stock to further move said drum longitudinally against the actionbof said spring means to thereby disengagel said/driving member from .said driven member to permit relative rotary movement of the drum with respect to said clutch assembly.

5. Apparatus such as deilned in claim 4 wherein said clutch assembly also includes a projection attached to said driving member and rotatable therewith, said projection being-mounted to cooperate with the end of said scanner drum, a recess in the end of said scanner drum for receiving said projection, whereby said. scanner drum may be driven by said projection when said driving member is disengaged from said ydriven member.

6. Apparatus such as defined in claim 4 where-v in said clutch assembly also includes a roller attached to said driving member and rotatable therewith, said roller being arranged to cooperate with the end of said drum, a recess in the end oi' said drum for receiving said roller, whereby said drum may be driven by said roller when said driving member is disengaged from said driven member and whereby a predetermined orientation of the drum with respect tothe clutch assembly may be maintained.

7. A facsimile transmitting apparatus including a scanning drum, driving means for rotating said drum including a motor and a clutch assembly, a head spindle associated with said clutch assembly for rotatably supporting one end of said drum, a tail stock assembly for rotatably supporting `the other end oi said drum, said clutch assembly including a driving and a driven clutch member, means for rotating the driving` member by said motor, spring means for normally causing the driving. and driven members to be engaged whereby the driven member may clutch face associated with said driven member, said second clutch face being arranged to coopcrate with the said one end of said scanner drum, means including said tail stock assembly i'or moving said drum longitudinally on said said driving member from said driven member to thereby permit relative rotary movement oi the scanner drum with respect to the driving member oi said clutch assembly.

8. Apparatus such as denned in claim 7 wherein said clutch assembly also includes a roller attached to said driving member and rotatable therewith, said roller being mounted with its axis of rotation normal to the rotational axis of said clutch assembly and arranged to cooperate with the end of said scanner drum, a radial recess in the end of said drum for receiving said roller, whereby said drum may be driven by said roller when said driving member is disengaged from said driven member and whereby a predetermined orientation of the drum with respect to the driving member of the clutch assembly may be maintained.

9. A facsimile apparatus including a drum, means for normally supporting said drum between a rotating clutch assembly and a tail stock assembly, said drum being provided at each end with an axial recess, a head spindle associated withv such\clutch assembly and a tail spindle associated with said tail stock assembly for cooperating with the axial recesses in said drum, means for moving said tail stock spindle longitudinally towards said clutch Aassembly a prede,

termined amount to cause said spindles to engage said recesses to thereby support said drum and to lift said drum from said normal support means, said clutch assembly including a clutch face arranged to cooperate with one end of said drum, said longitudinal movement being effective to cause said drum to move longitudinally on said head spindle to thereby cause the drum to engageL said lclutch face whereby said drum may be rotated by said clutch assembly.

10. Apparatus such as defined in claim .9

vwherein said clutch face is attached to a driven member, a rotating driving member, a second` clutch arrangement between said driving member and said driven member, spring means for normally causing engagement of said second clutch to cause the driven member to be rotated by said driving member, and means including said tail stock assembly for imparting a, second longitudinal movement to said drum in the direction of the clutch assembly to thereby stress said spring to disengage said second clutch whereby said drum may rotate relative to said driving member.

11. Apparatus such as dened in claim 9 wherein said clutch face is attached to a driven member, a rotating driving member, a second clutch arrangement between said driving member and said driven member,v spring means for normally causing engagement of said second clutch to'cause the driven member to be rotatedv by said driving member, means including said tail stock assembly for imparting a further 1on gitudinal movement to said drum in the direction of the clutch assemblyto stress said spring and f to thereby disengage said second clutch whereby be rotated by said driving member, a secondy head spindle to therebyl engage the scanner drum with said second clutch face whereby said drum may be rotated by said driven member, and means including said last named means for further moving said drum longitudinally against the action or said spring means to disengage said drum and driven member may rotate relative to said driving member, and means including a projection attached to said driving member,

the projection being positioned to cooperate with vided at each end with a circular axial recess, a head spindle associated with said clutch assembly and a tail spindle associated with said tail stock assembly for cooperating with the axial recesses, means for sliding said tail stock spindle longitudinally a predetermined amount towards said clutch assembly to cause said spindles to engage said recesses to thereby lift said drum from the bracket support means whereby the drum may be supported by said spindles, said clutch assembly including a friction clutch face arranged to cooperate with one end of said drum, said predetermined longitudinal movement of said drum on said head spindle being eiective to engage the said one end of the drum with said clutch face whereby said drum may be rotated by said clutch assembly.

13. Apparatus such as defined in claim l2 wherein said clutch face is attached to a driven member, a rotating driving member, a second clutchv arrangement between said'driving member and said driven member, spring means for normally causing engagement oi' said second clutch to cause the driven member to be rotated by said driving member, means including said tail stock assembly for imparting a second longitudinal movement to said tail stock spindle and drum in the direction of the clutch assembly to thereby stress said spring to disengage said second clutch whereby said drum and driven member may rotate relative to said driving member, and means including a roller attached to said driving member, said roller being positioned to cooperate with a radial recess in the said one end of said drum whereby the second longitudinal movement will cause said roller to engage the recess toprovide a positive driving action and to maintain a desired orientation of the drum with respect to said driving member.

14. A tail stock assembly for a facsimile apparatus including a longitudinally movable spindle, spring means for urging said spindle in a retracted position, a ratchet member slidably positioned on said spindle, spring means for urging said ratchet along said spindle in a predetermined direction, pawl'means for engaging said ratchet to longitudinally move said spindle against the action of said first named spring by driving force transmitted through said second spring, said pawl means being adapted to engage a second steplon said ratchet to longitudinally move said spindle further from its retracted position against the action of said first spring, and means for retaining said ratchet and spindle in either of the two positions.

15. A tail stock assembly for a facsimile transmitting apparatus including a longitudinally movable spindle, a rst spring means for urging said spindle in a predetermined retracted position, a two step ratchet member slidably positioned on said spindle, a second spring means for urging said ratchet along said spindle in a predetermined direction, a pawl positioned to engage a first step on said ratchet to longitudinally move said spindle against the action of said first named spring by driving force transmitted through said secondspring, said pawl, when retracted, being adapted to engage a second step on said ratchet to longitudinally move said spindle further from its retracted position against the action oi' said first spring. and means cooperating with said ratchet for retaining said ratchet and spindle in either oi the two positions, said retaining means being pivoted whereby the ratchet may be released in order that the spindle may be returned to its retracted position by said ilrst named spring.

16. A facsimile apparatus including a continuously rotating driving member, a clutch assembly associated with said driving member including a driven member, cooperating clutch faces between said driving member and said driven member, spring means for normally engaging said clutch faces to rotate said driven member by said driving member, a drum, a second clutch face on said driven member arranged to'cooperate with said drum, a head spindle associated With said clutch assembly for supporting one end of said drum, a tail spindle for supporting the other end of the drum, means for longitudinally moving said tail spindle and said drum whereby said drum may engage said second clutch face on said driven member to thereby cause rotation ot said drum, means for imparting further longitudinal movement to said tail spindle and to said drum to stress said clutch spring to thereby disengage said driving member from said driven member in order that said drum and driven member may rotate relative to said driving member, and means responsive to the latter longitudinal movement of said drum for provid ing positive driving engagement between said drum and driving member.

17. A facsimile transmitting apparatus includf ing a continuously rotating driving member, a

clutch assembly associated with said driving memberincluding a driven member, cooperating clutch faces between said driving member and said driven member, spring means for normally engaging said clutch faces to rotate said driven member by said driving member, a scanner drum for supporting the subject matter to be scanned, a second clutch face on said driven member arranged to cooperate with one end of said drum, a head spindle associated with said clutch assembly for rotatably and slidably supporting one end of said-drum, a longitudinally movable tail spindle for supporting the other end of the drum, means for longitudinally moving said tail spindle and said drum whereby said drum may slide on said head spindle to engage the end of said drum with the clutch face on said driven member to thereby rotate said drum, means for imparting a further longitudinal movement to said tail spindle and to said drum to stress said clutch spring to thereby disengage said driving member from said driven member in order that said drum and driven member may rotate relative to said driving member, a roller attached to said driving member, said roller being positioned with its axis of rotation normal to the axis of said head spindle and arranged to cooperate with the end of said drum, a radial recess in the end of said drum, whereby the relative rotation of the drum with respect to the driving member will permit engagement of the roller with the recess in the end of the drum to provide a positive drive and assure a predetermined orientation of the drum with respect to the driving member.

MAURICE ARTZT. 

